Hand wrenches in the form of a combination hand tool, which are usable as screw drivers and as socket wrenches, are known, for example, from German published application DE 2 117 797. A hand tool is described here which, in addition to a screwdriver tip, has a socket wrench socket positively connected thereto, one being able to select which hand tool end is brought to use by axial displacement against the action of a coiled spring attached to the screwdriver shaft.
This combination known up to this point of differently dimensioned functional ends on a hand tool is already restricted in that it does not provide combining two functional ends for a machine-usable tool. In the present hand tool, a Phillips head screwdriver or a slotted screwdriver end or an outerly engaging functional end, such as a polygonal socket wrench end, may only be selected and brought to use manually. Furthermore, to use the screwdriver end, the socket wrench attachment must be displaced vertically each time manually against the coiled spring pushed onto the shaft for the friction lock between socket wrench end and screwdriver end, which on one hand represents a significant obstruction in normal use and on the other hand means that the socket wrench attachment always lies above the screw head as the tool is rotated, so that it is not possible to visually check the rotational movement and the snug fit of the tool. A machine-bound use is thus also not possible without further measures.
In view of the foregoing, at least one object of the invention is therefore to provide a combination attachment for machine screws which allows a combination of various socket-functional screw ends and is usable machine bound while concurrently improving the handling of the selected tool head. In addition, other objects, desirable features, and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.